IR 05000213/1985022
| ML20137B500 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 11/14/1985 |
| From: | Mccabe E, Swetland P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20137B409 | List: |
| References | |
| 50-213-85-22, NUDOCS 8511260284 | |
| Download: ML20137B500 (6) | |
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U.S. NUCLEAR REGULATORY COMMISSION l
REGION I
MEETING REPORT Report No.
50-213/85-22 Docket No.
50-213 License No.
OpR-61 l
Licensoo:
Connecticut Yankee Atomic Power Company P. O. Box 270 Hartford, CT 06101 Fact 11ty:
Haddam Neck Plant, Haddam, Connecticut Meeting Dato: October 31, 1985 Roported by:
$4 khde h 84l64l97 Paul 0. $~watTin~d Senlor Rostdent Inspector bate
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Approved by:
h^ kh if l04lII E~OcciboTclTef, Reactor Projectrloctfon, 3B 0ato
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Summa ry,:
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A management mooting was conducted at NRC Region I on October 31, 1985, to dis-l cuts auxtitary foodwater (AFV) system wiring problems recently identified at l
Haddam Neck. The specific problem concerned the cross-wiring of power supplies to four of six solenold-operated AFW actuation valves, Poor installation con-
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l trols and inadequate post-modification testing resulted in returning the system to operation with the cross wired circuits.
System operability was unaffected l
in this case.
The Itcensee presented a description of the event, its signi-ficance and causal factors, an' proposed corrective actions rotated to (1) Im-d proved installation controls (2) improved phased testing requirements, and (3)
the development of an appropriate list of old modifications to be specifically reviewed for potential component testing inadequacies. NRC Rogton I concurred
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with the Ilconsoo's ovaluation that the AFW system remained operable.
The
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Itconsee agrood to provide, for NRC Region ! review, further details regarding the implementation of the planned corrective actions.
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DETAIL _S 1.
Meeting Attenden i
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Connoc_ticut Yankee l
R. H. Gravos, Station Superintendent J. H. Ferguson, Unit Superintendent i
E. J. Mroczka, Vice-Prosident, Nucioar Operations J. M Powers, Licensing Engineer R. J. Schmidt, Supervisor, Special Projects
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G. H. Tylinski, Assistant Engineering Supervisor
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NRC Region 1 i
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t L. H. Dettenhausen, Chief, Operations Branch, Division of Reactor Safety l
S. D. Ebnotor, Director, DRS I
W. F. Kano, Deputy Director, Division of Reactor Projects DRP
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E. C. McCabo, Chief, Reactor Projects Section 30, ORP
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R. W. Starostocki, Director, DRP c
l P. D. Swetland, Sontor Resident Inspector
2.
Mooting Presentat_fon F
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The licensee presented his analysis of the recently identified auxiliary l
feedwater (AFW) miswiring problems.
Included in the discussion were the l
cause and significance of the specific deficiencies, and the offect of the
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causal factors on the quality of other similarly performed modifications
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and on other licenson activities currently engaged in verification of I
plant design. A prosentation outlino provided by the licensee is included l
as Attachment 1 to this report.
3.
Corrective Actions During the meeting, proposed improvements in the licensee's modification
control program were discussed regarding (1) the delineation of installation controls, and (2) the delineation of phased testing
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In addition, the licensoo proposed to develop an
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appropriate set of old modifications which may be subject to similar design change control problems and to verify by rotest or review of
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oxisting test documents the continued operability of those modified
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components, r
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NRC Position i
NRC Region ! concluded that the Ilconsco's review of this matter was
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thorough and appropriate to the significanco of the event.
The proposed I
corrective actions, however, were not sufficiently developed at this time i
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to provide assurance of the continued offectiveness of those measures, i
Consequently, the licensee was requested to provido a written responso for l
l NRC Region I review, including the details and schedule for implementation l
of the proposed corrective actions.
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i Connecticut Yankee Atomic Power Company
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Management Meeting l
USNRC Region I October 31, 1985 Reference:
Special Inspection 50-213/85-20 - Automatic Auxiliary Feedwater Actuation System
A.
Probinm Doncription:
On November 2, 1984 during the surveillance test for the auxiliary feedwater system, 2 main feedwater bypass valves failed to open.
The causo was determined to be sticking solonoid oporated valves (SOV's).
To alloviate the problem, l
por manufacturer's recommendations, more frequent cycling of
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l the valvos was proposed.
This was accomplished by implo-menting Proventativo Maintenanco Proceduro (PMP)-9.2-45. -
During the performance of this proventative maintenance proceduro, fusos protecting circuits which actuato the SOV's i
for the feodwater bypass valves and AFW Terry Turbine system steam admission valves, were individually removed to doenergize the circuits and cause a change in position of the SOV's and in turn open the feedwater bypass valvon and ntoam adminnion valvon.
An error was discovered when a fuso
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thought to be associated with the (A) Terry Turbino steam adminnion valve wan ?ulled resulting in startup of the (B)
Terry Turbino.
Furt1or investigation revealed that a l
nimilar cross-connection problem existed in two of the four l
AFW nyntem bypass valves.
Additionally, during the parformanco of the proceduro, one of the four solonoid
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oporated valvos (SOV's) for the foodwater bypans valvos failed to chango position and allow the bypann valvo to open.
The attached wiring diagram (skotch) illustratos the dotnils of the error which caused the improper valvo operations.
The following is.a chronology of events from implomontation of the PDCR which addod the automatic initiation featuro to the auxiliary foodwater syntom through to the final disposi-tioning of intorim splicing.
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The original plant design chango was a renuit of a post-THI requiremont to incorporato auto-initiation of I
the auxiliary foodwater syntom.
The initial donign
chango incorporated a control grado syntom which would lator be upgraded to safety grado.
The majority of
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the modifications contored around SOV and actuation logic circuitry installation.
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o Durinn the following refueling outage, the automatje initiation system won upgraded to safety-grade.
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involved upgrados to the steam generator levnl
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instrumentation and the 80V's.
With regard to the
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l SOV's, complicationc arono in wiring thn replacement
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SOV's because their alcetrical pigtails wore shorter
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than those on the original SOV's.
A Design Chango
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Notico (DCN) was initiated to allow the interim uno of I
an intermediato section of splicod-in wiring.
Subsequent to the Sov change-out, including wiring, a
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QC inspection revealed that identification tags woro not in place on the SOV's or their wiring.
Wo believe that a tagging error, as opposed to a wiring error,
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occurred at this timo.
Thus at thin timo, the system l
l was installed in full compliance with the design,
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however, with SOV's (4 out of 6) mislaboled.
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o During the 1903 refueling outage, final disposition with respect to the spliced-in sections of wiring was
accomplished by a rowiring of the SOV's.
At this time, as at present, the SOV ID tags were in the improper
l position in 4 of 6 instances.
Wiring was done to the l
improperly tagged valvos in accordance with design l
drawings resulting in the cross-connections being
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incorporated.
Based on the above, we believe the design was correctly f
incorporated initially.
A review of the design drawings
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show they accurately reflect the intended design.
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l surveillance test performed on the auxildary foodwater i
l system did not detect the error because overall system I
operability was not and is not affected.
No divisional l
separation was violated by the wiring error sinco it
l occurrod in the wiring between main control board terminal
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blocks and the adjacontly mounted SOV's.
D.
Cauno of Problem:
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The design change was implomonted in three distinct phases.
The first phaso resultad in a control grado system an OA Category I solenoid valvos woro not available.
Both pnoumatic and cloctrieni drawingn woro required to implement Phano I.
When considered r
collectively, the information contained on the i
pneumatic plus electrien1 drawings was adoquato to allow the installation to be performed correctly.
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Phaso 2 consisted of replacing the existing control grade solonoid valvon with OA Category I solenoid valvos.
The solanoid valvon woro of a similar configuration pneumatien11y.
No additional pneumatic
rowork was required.
Thoroforo, the pnoumatic drawings l
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woro not issued.
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Phase 3. changed out the wiring to remove the dual O
splices.
No pneumatic rework was required.
The electrical drawings taken by themselves did not contain sufficient information to recognize that there was a problem with mislabeling.
The rewiring was completed according to the electrical drawings and incorrect labels.
o The testing that followed Phase 3 was a system test and did not test the individual components.
C.
Corrective Action:
Completed Actions A memo from the Senior Vice President - Nuclear o
Engineering and Operations to all supervisory personnel has been issued detailing the root cause and the need for phased testing.
A memo from the Vice President - Nuclear Operations was o
issued requiring "As-Built" verifications prior to the testing phase of any modifications.
Training on the philosophy of testing (the phased o
approach) has been given to Millstone and Connecticut Yankee Engineering personnel, The Connecticut Yankee operators are aware of the o
miswiring of the SOV's and, therefore, will not be misled if a situation should exist for emergency actions.
Planned Actions
.The wiring and labeling will be corrected during the o
upcoming refueling outage.
A memo from the Senior Vice President - Nuclear o
Engineering and Operations to all supervisory personnel will be issued by November 15, 1985 explaining the need for sufficient drawing detail or instructions in order to insure pe'rsonnel can correctly install, inspect and label multiple, identical components.
D.
Generic Implications:
Plant Design Changes will be reviewed to determine which design changes have the unique characteristic whereby a component installation error could significantly mislead personnel during an emergency.
If adequate component testing was not completed during its installation, the component testing will be completed during the next refueling outage scheduled for January 198.-4-
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WIRING DIAGRAM AUXILIARY FEEDWATER AUTOMATIC INITIATION SOLENOIDS HIC-1301-1 TERMINAL
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4 AFW BLOCK 18KX
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A B D,' I A3-SGILX4
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C A3N 9 3 3,",
HICV-1301-1 PIC 1206A
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Q,,' p B3-SG2LX4 l
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HIC-1301-2 S O V-12068 PICV-
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1206A
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S OV-1301 2 HICV-1301 2 PIC-12068
+ HIC-1206B
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HIC-1301 3 SOV-1206A PICV-1206 B SOV.
1301-4
+ HICV-1301 3 C3 SG3LX4 hic-1301-4 oj o Similar r
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o Above D3-SG4LX4 O
"3 D3N SOV-1301-3 HICV-1301-4 HADDAM NECK PLANT SEPTEMBER 1985
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